Liquid crystal display (LCD) screens are commonly back-lighted to make them easier to read. Known liquid crystal displays (LCD) with backlighting commonly include a core of LCD material between sheets of glass. A backlighting element produces light to illuminate LCD material is disposed at the back of the glasses. From a power consumption point of view, LCD backlighting is far from efficient. For example, while the backlighting element is set to a bright level to illuminate the LCD material, depending on the image values to be displayed in pixels, the LCD material may be in a twisting configuration which causes a substantial portion of light passing through the LCD material to be blocked by the second polarizer, resulting in inefficient use of backlighting. In fact, power consumption of LCD backlight may account for a large portion of the overall power consumption of a display device. The energy inefficiency due to LCD backlighting may lead to a series of power problems, including, shorter operating time than the capacity of a battery could have provided, frequent charging and discharging of the battery and hence reduced battery life, which may be particularly problematic for displays in portable devices, e.g., mobile phone. Backlight control is therefore an important feature for display systems.